Improvement in rotary svalves



'eccentric on the main shaft.

UNITED STATES tPATENT OFFIon.

JAMES J ENKS, OFDETROI'I, MICHIGAN, ASSIGN OF ONE-HALF HIS RIGHT rIO GEORGE A. J EN KS, OF SAME PLAGE.

IMPROVEMENT IN ROTARY IJVALVES.

Specification forming part of Letters Patent No. 187,638, dated, February 20,1877; application led october 31, 1876.

To all 'whom it may concern Y Be it known that I, JAMES JENKS, of Detroit, in the county of Wayne and State of Michigan, have invented an Improvement in Steam-Engines, of which the following is a speciiication The nature of my invention relates to an improvement in that class of rotary steamvalves which are provided with a hollow vrotary balance-valve and an internal cut-03d` valve; and it consists in the combination, construction, and arrangement of the several parts, as fully hereinafter explained.

Figure l is a perspective view of a steamchest provided with my improved cut-off valve, which is shown as to be operated by an Fig. 2 is a crosssection at x cv. Fig. 3 is a perspective view of the cut-oh" valve.

In the drawing, A represents a circular valve-case, having a steam-inlet, a, at the top,

' i into which a steam-pipe from the generator is tapped, or otherwise connected. 1n the bottom two steam-ports, b b, are cut, leading into a passage, c, communicating with the cylinder. lf the engine is ttcd with but one valve and valve-case, the passage cis divided by a partition, as at c', Fig. 2; but where there is a valve at each end, as there should be if economy in the use of steam be considered, then the passage c should be open to both ports b. B is the main valve, in the form of a hollow cylinder, closed at one end, and axially mounted on a stem, B', passing through a stuffingbox in the adjacent head of the case, with an arm, C, at the extremity, connected by a rod, I), with an eccentric on the main shaft, by which the said valve is oscillated on its axis. The valve has a large opening cut in its top, longitudinally, through which steam may always pass into the interior thereof. At the bottom are two longitudinal ports, b b', which alternately disclose and cover the ports b.

Within the main valve a spidershaped valve, E, ispsleeved, having three radial ribs, d d d', the last of which is an extended segment, which forms a valve, which, in its oscillation, may partially or entirely close the ports b ofthe malin valve. The wings of this valve arc perforated, so that steam may pass through to the ports@ of themain valve. The pressure being equallgupon all parts of the two valves, they are practically balanced.

The cut-off valvev is provided with a head or disk at one end, and is axially mounted on a spindle, E', passing through a stufng-box in the adjacent head of the valve-case, and is fitted with an arm, F, at its outer end, which may be connected with an eccentric on the main shaft by a rod, G, in case it is intended to be used as a fixed cut-off, or with a governor,- if the said valve E is designed to be used for regulating the speed of' the engine. But what l prefer toydo is to place a valve-case and valves at each end of the steam-cylinder, use each valve B to admit steam to its endl of the cylinder, and, by the combination of the eccentric andi a governor, in any convenient way, to operate'the valve E, so that it will serve as a cut-oft' to permit of expansion in the cylinder, and as a speed-regulator, thus making it what is commonly known as an automatic cut-oli'.

What I claim as my invention is- In an oscillating valve, the combination, with the case A, having the passages a, b, and c, of the hollow valve B, provided with a large opening at its top, and the ports b in the bottom thereof, and the spider-shaped valve E, having the Iq ierforated ribs or wings d d d', constructed.l and arranged substantially as described andfshown.

JAMES JENKS. Witnesses:

H. F.EBERTS, WM. l?. SPALDING. 

